The present disclosure generally relates to appliances, and more particularly to a temperature control system for an oven.
Current technologies for controlling the temperature of an oven typically rely upon feedback from a temperature sensor in the controlled space of the oven cavity. The temperature, reported by the sensor, is the temperature of the sensor itself, which is primarily influenced by one or more heating elements, the thermal energy of the oven surfaces, objects within the oven cavity, and the air temperature within the oven cavity. It is also influenced by air flow through the oven cavity, the opening and closing of the oven door, the position of the temperature sensor, the mass of the sensor, the position of oven vents and potentially other effects.
Temperature sensors, such as resistive temperature devices (“RTD”) are mounted within the oven cavity and are used to measure the temperature value within the oven cavity. In some cases, the sensors can be coupled to the walls of the oven for structural support, while the purpose is sensing the temperature value within the oven cavity. This information from the temperature sensor is used to estimate the temperature of the oven system for control of the oven. However, using one or more sensors to measure the temperature value from within the oven cavity can lead to a lack of oven performance accuracy. The environment inside the cavity is subject to a variety of events that affect the thermal state of the system, including different size loads, open doors or vents, different control setpoints, large temperature changes, and more. Those sources of variation in the oven environment can affect oven performance to the degree that the temperature measurement method is sensitive to such changes. More accurate measurement of the oven temperature improves the ability to raise and adjust the thermal energy level with consistency and predictability, enhancing cooking performance.
Typically, a resistive temperature device that hangs slightly below the inside top surface of the oven cavity is used to measure the temperature value in the oven cavity. Generally, oven controls using feedback from a single temperature sensor must use that single input to determine the state of the oven, particularly including the oven temperature. This can require that certain assumptions be made about the oven and the cooking conditions. These assumptions are not always correct or accurate due to the transitory nature of the oven and the variety of food loads. The temperature data from the air space inside the oven cavity does not always provide the best feedback for optimum cooking performance. It would be advantageous to control the cooking cycle of the oven by monitoring surface temperatures outside the oven cavity that affect cooking performance. It would also be advantageous to be able to take into consideration multiple sensor data in monitoring and measuring the temperature value of the oven cavity.
Accordingly, it would be desirable to provide a system that addresses at least some of the problems identified above.